memberd in Mac OS X 10.4 up to 10.4.2, in certain situations, does not quickly synchronize access control checks with changes in group membership, which could allow users to access files and other resources after they have been removed from a group.
https://exchange.xforce.ibmcloud.com/vulnerabilities/44465
http://www.vupen.com/english/advisories/2005/2256
http://www.securityfocus.com/bid/15252
http://securitytracker.com/id?1015125
http://secunia.com/advisories/17368
http://lists.apple.com/archives/security-announce/2005/Oct/msg00000.html